Manufacture of artificial tooth-crowns.



M. J. MURRAY.

MANUFACTURE OF ARTIFICIAL TOOTH CROWNS. APPLIOATION FILED-FEB. 25, 1911.

\M a G 1) 1) /7 W" a a Wiinessea: v [wentm' @W W MICHAEL J. MURRAY, OF NEW YORK, N. Y.

MANUFACTURE OF ARTIFICIAL TOOTH-GROWNS.

Specification of Letters Patent.

Application filed February 25, 1911.

Patented Apr. 8, 1913. Serial No. 610,794.

To all whom, it may concern:

Be it known that I, MIoHAEL J. MURRAY. a citizen of the United States, and resident of the borough of Manhattan, in the city and State of New York, have invented a new and useful Improvement in the Mannfacture of Artificial Tooth-Crowns, of which the following is a specification.

This invention relates to certain improvements in the manufacture of artificial tooth crowns and consists in an artificial tooth crown having a cavity therein provided with an unglazed lining and the method of pro ducing the same.

In the accompanying drawings, Figure 1 represents in top plan a portion of a mold bar showing one way of introducing a coating of non-glazing material into the cavity of an artificial tooth crown. Fig. 2 is a similar View showing another way of introducing the coating of non-glazing material into the cavity in the tooth crown. Fig. 3 is a section taken in the plane of the line AA of Fig. 1, Fig. 1 is a section taken in the plane of the line BB of Fig. 2. Fig. 5 is a section taken in the plane of the line C-C of Fig. 3, Fig. 6 is a section taken in the plane of the line DD of Fig. 4, Fig. 7 is a longitudinal section from front to rear taken through a completed artificial tooth crown, and Fig. 8 is a plan view of the completed artificial tooth crown, looking toward the base thereof.

The artificial tooth crown is denoted by 1. Its cavity in the base 2, for receiving a pin or other fastening means, is provided with a lining 3 of unglazed material, such, for in stance, as sile One method of carrying out my invention is to coat a fusible pin 4 carried by the mold bar 5, with a non-glazing material, such, for instance, as silex, and introduce the so coated portion of the pin into the cavity in the tooth crown, so as to bring the material into contact with the walls of the cavity before the tooth crown is burned. The parts which cement may be permanently united when used for securing the tooth crown to the part to which it is to be attached.

Another way of introducing the coating of non-glazing material into the cavity in the tooth crown before it is burned, is by inserting a fusible cylinder 6 covered with a coating of non-glazing material, over a nonfusible pin 7 projecting from the bar 5 and then inserting the pin with its coated fusible cylinder into the cavity in the tooth crown before the crown is burned. The parts are then inserted into a furnace where the tooth crown is burned and the fusible cylinder is burned away, thus leaving the cavity provided with an unglazed lining suitable for the attachment of the cement as above described. f It is to be understood that the above are only two of the ways that the cavities in the tooth crown can be coated preparatory to the burning of the tooth crown.

What I claim is:

The method of forming an artificial tooth crown with the walls of its cavity provided with a coating of unglazed material, such as silex, consisting in coating a fusible element with a non-glazing material and introducing the same into the cavity before the crown is burned and then burning the crown for burning the non-glazing material into the walls of the cavity and destroying the fusible element.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two witnesses, this twentyfirst day of February 1911.

MICHAEL J. MURRAY.

Witnesses:

F. GEORGE BARRY, HENRY G. THIEME.

Copies of this patent may be obtained for five cents each, by addressing the Washington, D. 0.

Commissioner of Patents, 

